package com.gzs.learn.admin.interceptor;

import com.gzs.learn.admin.common.annotation.RepeatSubmit;
import com.gzs.learn.admin.common.utils.ServletUtils;
import com.gzs.learn.common.AjaxResult;
import com.gzs.learn.common.util.JsonUtil;
import org.springframework.web.method.HandlerMethod;
import org.springframework.web.servlet.HandlerInterceptor;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.lang.reflect.Method;

/**
 * 防止重复提交拦截器
 *
 * @author guanzhisong
 */
public abstract class RepeatSubmitInterceptor implements HandlerInterceptor {
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        if (handler instanceof HandlerMethod) {
            HandlerMethod handlerMethod = (HandlerMethod) handler;
            Method method = handlerMethod.getMethod();
            RepeatSubmit annotation = method.getAnnotation(RepeatSubmit.class);
            if (annotation != null && isRepeatSubmit(request)) {
                AjaxResult ajaxResult = AjaxResult.error("不允许重复提交，请稍后再试");
                ServletUtils.renderString(response, JsonUtil.toJSONString(ajaxResult));
                return false;
            }
            return true;
        }
        return true;
    }

    /**
     * 验证是否重复提交由子类实现具体的防重复提交的规则
     *
     * @param request
     * @return
     * @throws Exception
     */
    public abstract boolean isRepeatSubmit(HttpServletRequest request);
}
